linux/drivers/clk/ti/clk.c

456 lines
11 KiB
C

/*
* TI clock support
*
* Copyright (C) 2013 Texas Instruments, Inc.
*
* Tero Kristo <t-kristo@ti.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed "as is" WITHOUT ANY WARRANTY of any
* kind, whether express or implied; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/clkdev.h>
#include <linux/clk/ti.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/list.h>
#include <linux/regmap.h>
#include <linux/bootmem.h>
#include "clock.h"
#undef pr_fmt
#define pr_fmt(fmt) "%s: " fmt, __func__
struct ti_clk_ll_ops *ti_clk_ll_ops;
static struct device_node *clocks_node_ptr[CLK_MAX_MEMMAPS];
static struct ti_clk_features ti_clk_features;
struct clk_iomap {
struct regmap *regmap;
void __iomem *mem;
};
static struct clk_iomap *clk_memmaps[CLK_MAX_MEMMAPS];
static void clk_memmap_writel(u32 val, void __iomem *reg)
{
struct clk_omap_reg *r = (struct clk_omap_reg *)&reg;
struct clk_iomap *io = clk_memmaps[r->index];
if (io->regmap)
regmap_write(io->regmap, r->offset, val);
else
writel_relaxed(val, io->mem + r->offset);
}
static u32 clk_memmap_readl(void __iomem *reg)
{
u32 val;
struct clk_omap_reg *r = (struct clk_omap_reg *)&reg;
struct clk_iomap *io = clk_memmaps[r->index];
if (io->regmap)
regmap_read(io->regmap, r->offset, &val);
else
val = readl_relaxed(io->mem + r->offset);
return val;
}
/**
* ti_clk_setup_ll_ops - setup low level clock operations
* @ops: low level clock ops descriptor
*
* Sets up low level clock operations for TI clock driver. This is used
* to provide various callbacks for the clock driver towards platform
* specific code. Returns 0 on success, -EBUSY if ll_ops have been
* registered already.
*/
int ti_clk_setup_ll_ops(struct ti_clk_ll_ops *ops)
{
if (ti_clk_ll_ops) {
pr_err("Attempt to register ll_ops multiple times.\n");
return -EBUSY;
}
ti_clk_ll_ops = ops;
ops->clk_readl = clk_memmap_readl;
ops->clk_writel = clk_memmap_writel;
return 0;
}
/**
* ti_dt_clocks_register - register DT alias clocks during boot
* @oclks: list of clocks to register
*
* Register alias or non-standard DT clock entries during boot. By
* default, DT clocks are found based on their node name. If any
* additional con-id / dev-id -> clock mapping is required, use this
* function to list these.
*/
void __init ti_dt_clocks_register(struct ti_dt_clk oclks[])
{
struct ti_dt_clk *c;
struct device_node *node;
struct clk *clk;
struct of_phandle_args clkspec;
for (c = oclks; c->node_name != NULL; c++) {
node = of_find_node_by_name(NULL, c->node_name);
clkspec.np = node;
clk = of_clk_get_from_provider(&clkspec);
if (!IS_ERR(clk)) {
c->lk.clk = clk;
clkdev_add(&c->lk);
} else {
pr_warn("failed to lookup clock node %s\n",
c->node_name);
}
}
}
struct clk_init_item {
struct device_node *node;
struct clk_hw *hw;
ti_of_clk_init_cb_t func;
struct list_head link;
};
static LIST_HEAD(retry_list);
/**
* ti_clk_retry_init - retries a failed clock init at later phase
* @node: device not for the clock
* @hw: partially initialized clk_hw struct for the clock
* @func: init function to be called for the clock
*
* Adds a failed clock init to the retry list. The retry list is parsed
* once all the other clocks have been initialized.
*/
int __init ti_clk_retry_init(struct device_node *node, struct clk_hw *hw,
ti_of_clk_init_cb_t func)
{
struct clk_init_item *retry;
pr_debug("%s: adding to retry list...\n", node->name);
retry = kzalloc(sizeof(*retry), GFP_KERNEL);
if (!retry)
return -ENOMEM;
retry->node = node;
retry->func = func;
retry->hw = hw;
list_add(&retry->link, &retry_list);
return 0;
}
/**
* ti_clk_get_reg_addr - get register address for a clock register
* @node: device node for the clock
* @index: register index from the clock node
*
* Builds clock register address from device tree information. This
* is a struct of type clk_omap_reg. Returns a pointer to the register
* address, or a pointer error value in failure.
*/
void __iomem *ti_clk_get_reg_addr(struct device_node *node, int index)
{
struct clk_omap_reg *reg;
u32 val;
u32 tmp;
int i;
reg = (struct clk_omap_reg *)&tmp;
for (i = 0; i < CLK_MAX_MEMMAPS; i++) {
if (clocks_node_ptr[i] == node->parent)
break;
}
if (i == CLK_MAX_MEMMAPS) {
pr_err("clk-provider not found for %s!\n", node->name);
return IOMEM_ERR_PTR(-ENOENT);
}
reg->index = i;
if (of_property_read_u32_index(node, "reg", index, &val)) {
pr_err("%s must have reg[%d]!\n", node->name, index);
return IOMEM_ERR_PTR(-EINVAL);
}
reg->offset = val;
return (__force void __iomem *)tmp;
}
/**
* omap2_clk_provider_init - init master clock provider
* @parent: master node
* @index: internal index for clk_reg_ops
* @syscon: syscon regmap pointer for accessing clock registers
* @mem: iomem pointer for the clock provider memory area, only used if
* syscon is not provided
*
* Initializes a master clock IP block. This basically sets up the
* mapping from clocks node to the memory map index. All the clocks
* are then initialized through the common of_clk_init call, and the
* clocks will access their memory maps based on the node layout.
* Returns 0 in success.
*/
int __init omap2_clk_provider_init(struct device_node *parent, int index,
struct regmap *syscon, void __iomem *mem)
{
struct device_node *clocks;
struct clk_iomap *io;
/* get clocks for this parent */
clocks = of_get_child_by_name(parent, "clocks");
if (!clocks) {
pr_err("%s missing 'clocks' child node.\n", parent->name);
return -EINVAL;
}
/* add clocks node info */
clocks_node_ptr[index] = clocks;
io = kzalloc(sizeof(*io), GFP_KERNEL);
if (!io)
return -ENOMEM;
io->regmap = syscon;
io->mem = mem;
clk_memmaps[index] = io;
return 0;
}
/**
* omap2_clk_legacy_provider_init - initialize a legacy clock provider
* @index: index for the clock provider
* @mem: iomem pointer for the clock provider memory area
*
* Initializes a legacy clock provider memory mapping.
*/
void __init omap2_clk_legacy_provider_init(int index, void __iomem *mem)
{
struct clk_iomap *io;
io = memblock_virt_alloc(sizeof(*io), 0);
io->mem = mem;
clk_memmaps[index] = io;
}
/**
* ti_dt_clk_init_retry_clks - init clocks from the retry list
*
* Initializes any clocks that have failed to initialize before,
* reasons being missing parent node(s) during earlier init. This
* typically happens only for DPLLs which need to have both of their
* parent clocks ready during init.
*/
void ti_dt_clk_init_retry_clks(void)
{
struct clk_init_item *retry;
struct clk_init_item *tmp;
int retries = 5;
while (!list_empty(&retry_list) && retries) {
list_for_each_entry_safe(retry, tmp, &retry_list, link) {
pr_debug("retry-init: %s\n", retry->node->name);
retry->func(retry->hw, retry->node);
list_del(&retry->link);
kfree(retry);
}
retries--;
}
}
#if defined(CONFIG_ARCH_OMAP3) && defined(CONFIG_ATAGS)
void __init ti_clk_patch_legacy_clks(struct ti_clk **patch)
{
while (*patch) {
memcpy((*patch)->patch, *patch, sizeof(**patch));
patch++;
}
}
struct clk __init *ti_clk_register_clk(struct ti_clk *setup)
{
struct clk *clk;
struct ti_clk_fixed *fixed;
struct ti_clk_fixed_factor *fixed_factor;
struct clk_hw *clk_hw;
if (setup->clk)
return setup->clk;
switch (setup->type) {
case TI_CLK_FIXED:
fixed = setup->data;
clk = clk_register_fixed_rate(NULL, setup->name, NULL,
CLK_IS_ROOT, fixed->frequency);
break;
case TI_CLK_MUX:
clk = ti_clk_register_mux(setup);
break;
case TI_CLK_DIVIDER:
clk = ti_clk_register_divider(setup);
break;
case TI_CLK_COMPOSITE:
clk = ti_clk_register_composite(setup);
break;
case TI_CLK_FIXED_FACTOR:
fixed_factor = setup->data;
clk = clk_register_fixed_factor(NULL, setup->name,
fixed_factor->parent,
0, fixed_factor->mult,
fixed_factor->div);
break;
case TI_CLK_GATE:
clk = ti_clk_register_gate(setup);
break;
case TI_CLK_DPLL:
clk = ti_clk_register_dpll(setup);
break;
default:
pr_err("bad type for %s!\n", setup->name);
clk = ERR_PTR(-EINVAL);
}
if (!IS_ERR(clk)) {
setup->clk = clk;
if (setup->clkdm_name) {
clk_hw = __clk_get_hw(clk);
if (clk_hw_get_flags(clk_hw) & CLK_IS_BASIC) {
pr_warn("can't setup clkdm for basic clk %s\n",
setup->name);
} else {
to_clk_hw_omap(clk_hw)->clkdm_name =
setup->clkdm_name;
omap2_init_clk_clkdm(clk_hw);
}
}
}
return clk;
}
int __init ti_clk_register_legacy_clks(struct ti_clk_alias *clks)
{
struct clk *clk;
bool retry;
struct ti_clk_alias *retry_clk;
struct ti_clk_alias *tmp;
while (clks->clk) {
clk = ti_clk_register_clk(clks->clk);
if (IS_ERR(clk)) {
if (PTR_ERR(clk) == -EAGAIN) {
list_add(&clks->link, &retry_list);
} else {
pr_err("register for %s failed: %ld\n",
clks->clk->name, PTR_ERR(clk));
return PTR_ERR(clk);
}
} else {
clks->lk.clk = clk;
clkdev_add(&clks->lk);
}
clks++;
}
retry = true;
while (!list_empty(&retry_list) && retry) {
retry = false;
list_for_each_entry_safe(retry_clk, tmp, &retry_list, link) {
pr_debug("retry-init: %s\n", retry_clk->clk->name);
clk = ti_clk_register_clk(retry_clk->clk);
if (IS_ERR(clk)) {
if (PTR_ERR(clk) == -EAGAIN) {
continue;
} else {
pr_err("register for %s failed: %ld\n",
retry_clk->clk->name,
PTR_ERR(clk));
return PTR_ERR(clk);
}
} else {
retry = true;
retry_clk->lk.clk = clk;
clkdev_add(&retry_clk->lk);
list_del(&retry_clk->link);
}
}
}
return 0;
}
#endif
/**
* ti_clk_setup_features - setup clock features flags
* @features: features definition to use
*
* Initializes the clock driver features flags based on platform
* provided data. No return value.
*/
void __init ti_clk_setup_features(struct ti_clk_features *features)
{
memcpy(&ti_clk_features, features, sizeof(*features));
}
/**
* ti_clk_get_features - get clock driver features flags
*
* Get TI clock driver features description. Returns a pointer
* to the current feature setup.
*/
const struct ti_clk_features *ti_clk_get_features(void)
{
return &ti_clk_features;
}
/**
* omap2_clk_enable_init_clocks - prepare & enable a list of clocks
* @clk_names: ptr to an array of strings of clock names to enable
* @num_clocks: number of clock names in @clk_names
*
* Prepare and enable a list of clocks, named by @clk_names. No
* return value. XXX Deprecated; only needed until these clocks are
* properly claimed and enabled by the drivers or core code that uses
* them. XXX What code disables & calls clk_put on these clocks?
*/
void omap2_clk_enable_init_clocks(const char **clk_names, u8 num_clocks)
{
struct clk *init_clk;
int i;
for (i = 0; i < num_clocks; i++) {
init_clk = clk_get(NULL, clk_names[i]);
if (WARN(IS_ERR(init_clk), "could not find init clock %s\n",
clk_names[i]))
continue;
clk_prepare_enable(init_clk);
}
}